If we can override undefined in Javascript, where does 'void 0' takes value from? -


i know undefined isn't reserved keyword , 1 can make whatever wants it. can override example. if override undefined in javascript, void 0 takes value from?

try piece of code:

let undefined = 'test'; console.log(undefined); // prints out 'test' console.log(void 0); // prints out 'undefined'

at first glance, looks, javascript provides second version of undefined somewhere inside , returns result of void operator.

void 0 isn't pulling value undefined variable. it's returning primitive type undefined: https://developer.mozilla.org/en-us/docs/glossary/primitive.

your code defining variable same name -- not redefining primitive type itself. knowledge, can't done.

see more on question: is possible overwrite javascript primitive data type?


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